Crankpin grinder



Feb. 18, 1941. w. 1.. GROENE CRANKPIN GRINDER Filed May 120", 1940 2 Sheets-Sheet 1 WWW (4 KC td-4 3.? PM

Feb. 18, 1941. w, L, @OENE 2232,2223

CRANKPIN GRINDER Fi1 ed May 10, 1940' 2 ShetS-Sheet 2 54-0. 350. 3 o. a. I

Patented Feb. 18, 1941 camrmoamnria Willard L. Groene, Cincinnati, Ohio, assignor to The R. K. Le Blond Machine Tool Company, Cincinnati, Ohio, a corporation of Delaware Application my 10, 1940, Serial No; 334,407

This invention pertains to grinding machines and is particularly related to the type of grinding m'achinesused iorgrinding the crankpins of crankshafts'for 'multi-throw internal combustion engines. More particularly this invention pertains to a grinding machine capable of simultaneously machining a plurality of 'crankpin bearings of a' crankshaft in a singleoperation.

Another object of this'inve'ntion is to provide a crankpin grinding machine which is capable of grinding all of the pin bearings of a multi-throw internaloombustion' engine crankshaft in onejoperation in which each' of the'g'rinding wheels for each of the'crankpins may 'be fed independently to its. respective crankpin so as to properly size these bearing portions of the crankshaft.

Another object of this invention is to provide an orbital grinding machine in which a series of grinding wheels is provided, for each of the crankpins' of a multi-throw internal combustion engine crankshaft, which may be independently fed to each of the respective pin bearings to be ground during the simultaneous grinding of all of said bearing portions. a

Another object of this invention'is to provide in'a crankpin grinding machine, means to cause a series of grinding wheels to be simultaneously applied to all of the crankpin bearings of a multithrow crankshaft while said crankshaft is rotated on its line bearing axis during' flthe grinding pro ess.

Still another vide a crankpin grinding machine with a series of orbitally moving grinding wheel carriers which may be oscillated in synchronism with the rotation of the crankshaft to be ground so that each grinding wheel provided for each crankpinwili travel in an orbital path properly following the orbital movement of the crankpin bearings of the work crankshaft-as it-is rotated duringthe grinding operation. 1

It is also an object to provide in a grinding machine, having orbitally moving grinding wheel carriers, means whereby the grinding. wheels may be fed on said carriers to andfrom the crankpins to be ground independent of the orbital motion of said carrier.

A still further object of this invention is to provide, in a grinding machine for simultaneously grinding a plurality ofcrankpins on an internal combustionengine crankshaft, orbitallymoving grinding wheel carriers upon which are mounted a series of grinding wheels, one for each crankpin to be ground on said crankshaft, and to provide motive means for rotating the grinding wheels on each of said grinding wheel carriers. 7

Further features and advantages of this invention will appear fromthe detailed description of the drawings in which:

object invention is to pro 1 Figure I is a diagrammatic transverse section through aerankpin grinding machine for simultaneously grinding all of the crankpins of a multi-throw internal combustion engine crankshaft in a single operation, shown on the line I --I of Figure II.

Figure 11 is a diagrammatic front elevation, partly in section, on the line IIII of Figure I.

For illustrative purposes, this invention has been shown applied to grinding the four crankpin bearingsof a 'V-8 multi-throw crankshaft in'which eachof the crankpin bearings lie in a different indexed ,position about the line bearing axis of rotation of the crankshaft, that is each of the crankpin. bearings are circumferentially spaced at 90 about-thisaxis. The crankshaft C to be ground has the line bearing axis l, and the various pin bearings 2, 3, 4, and 5, which are suitably interconnected by means of the webs 6, as is usual for such crankshafts. This crankshaft C is shown chuckedon its line bearing axis I in suitable potchucks 6 carried on appropriate work spindles 1 journaled in suitable bearings in the upright frames I, mounted on top of the base .9 of the machine. 7

0n eachof these work spindles I, is fixed a gear l0 which gears are in mesh with respective idler gears ll journaled on suitable studs 12 fixed in the upright frames 0. a

Journaled in the base .3 of the machine is the lower master jcrankshaft ll upon the outer ends of which are fixed the drivinggears H which are in mesh with the idler gears ll. Journaled in the upright frames 8 is the upper master crankshaft l i which carries driving gears it on its outerends also in mesh with the idler gears II. The gearsv l0, l4, and I6 are all of the same diameter and number of teeth so that the work spindles I and the master crankshafts i3 and II rotate in exact synchronism when driven by themain drive motor l'l, mounted on the projection ll of the base I. "I'his'motor II has a driving pinion is driving the gear 20 of the compound gear !ll-Il, the gear II of this compound gear in turn driving into the driving gear II on the lower master crankshaft l3.

Each of these master crankshafts have the respective crankpins 2a, 3a, la, and 5a, corresponding in indexed position and stroke with those of the respective bearings 2, 3,- 4, and! of the crankshaft C to be machined. On these various pin bearings are mounted the grinding wheel carriers 22 mounted directly on the crankpins of the lower master crankshaft II by a suitable journal 23 and through a linkage connection 230 on the crankpins of the upper master crankshaft it. Thus these carriers 22 are moved in synchronized motion in proper timed-relation and position relative to the respective bearings I 2, I, i, and 5, to be ground on the crankshaft C.

pressure cylinder 26, which is fixed on the surface 26 of the carrier 22 by suitable screws 26. In this cylinder operates the piston 3| having a piston rod 22,'which is connected to the block 33, fixed on the underside of the grinding wheel housing 24. Fluid pressure may he applied to one or the other end of this cylinder 26, through suitable pipe lines 24 and 35 having pasageways opening outwardly and upwardly at the rear of the carriers 22 to which are connected the flexible pipe lines 34a and 35a to a manifold 26 which in turn is appropriately connected to hydraulic fluid pressure mechanism whereby fluid pressure may be distributed to the cylinders 28 for effecting independent reciprocatory feeding movement in thevarious grinding wheel housings 24 for feeding the grinding wheels 26 to each of the crankpins to be ground. On each of the housings 24 is fixed a bracket 36 having an adjustable stop screw 21 adapted to abut against the rear surface 22a of the grinding wheel carriers 22 so as to provide an accurate and positive stop for the infeed position of the grinding wheel 26 for each crankpin to be ground, so that each of the crankpins may be ground to precise dimensions independent of the feeding motions being effected at the other crankpins. In this way accurate sizingof all of the crankpins is independently accomplished for each crankpin independent of the diameter provided by each of the grinding wheels, thereby effecting a very accurate finished result for each of the crankpins.

a Each of the grinding wheels 26 is individually driven by its own electriemotorvilmounted on wits respective grinding wheel housing 24, each of driving means for each of the grinding wheels 26 in the respective grinding wheel housings 24.

All of thesecarriers 22 are kept in proper axial alignment lengthwise of the crankshaft to be machined by means of suitable side thrust plates 22a and 22b, provided on the sides of these carriers and which are all maintained in proper operating contact by means of suitable thrust plates 46, carried on studs 41 fixed in the upright support I, and adjusted in proper running- W contact-with the various tool carriers 22 by suitable adjusting screws 46 in a manner substantially as setforth in Patent Reissue Number 18,662, of William F. Groene and Harold J. Siekmann, issued November 22, 1932.

Having thus fully set forth and described my invention what I claim as new and desire to secure by United States Letters Patent is:

1. Ina crankpin grinding machine, a rotatable,

work spindle, a pair of master crankshafts, means for rotating said work spindle and mster crankshafts in synchronism, grinding wheel carriers mounted on the crankpins of said master crankshafts, a grinding wheel housing mounted on each of said carriers, a grinding wheel in each of said housings, means for rotating said grinding wheels, and means for moving said housings on said carriers to effect a feeding of said grinding wheels relative to said work spindle.

2. In a crankpin grinding machine, a rotatable world. spindle, a pair of master crankshafts,

means for rotating said'work spindle and mas- 'able work spindle, a pair of master crankshafts,

means for rotating said work spindle and master crankshafts in sy'nchronism, grinding wheel carriers mounted on the crankpins of said master crankshafts, a grinding wheel housing mounted on each of said carriers, a grinding wheel in each of said housings, means on each of said housings for driving said grinding wheels, and means on said carrier for moving said housings to eifect a feeding of said grinding wheels relative to said work spindle,

4. In a crankpin grinding machine. a rotatable work spindle, a pair of master crankshafts, means for rotating said work spindle and master crankshafts in synchronism, grinding wheel carriers mounted on the crankpins ofrsaid master crankshaftaia grinding wheel housing mounted on. each of said carriers, a grinding wheel in each of said housings, means for rotating said grinding wheels, means for independently feeding each of said housings on its respective carrier. and means for limiting said feeding motion of said housings on each of said carriers.

5. In a crankpin grinding machine, a frame, a rotatable work spindle journaled in said frame. a pair of master crankshafts journaled in said frame, means for rotating said work spindle and master crankshafts in synchronism, grinding wheel carriers mounted on the crankpins of said mastercrankshafts, grinding wheel housings movably mounted on said carriers. a grinding wheel in each of said housings, means on said housings for rotating said grinding wheels, and

means on said carriers for actuating said hous ings in feeding movements relative to said work spindle.

6. In a crankpin grinding machine, a frame, a rotatable work spindle Journaled in said frame,

a pair of master crankshafts Journaled in said frame, means for rotating said work spindle and master crankshafts in synchronism, grinding wheel carriers mounted on the crankpins of said master crankshafts, grinding wheel h usings slidably mounted on said carriers, .a grinding wheel in each of said housings, an electric motor on said housings for rotating said grinding wheels. and fluid pressure operated means on said carriers for actuating said housings in feed: ing movements relative to said 'work spindle.

' WILLARD L. GROENE. 

